1. Field of Invention
This invention elates generally to the petection of flying birds by preventing them from colliding with a transparent barrier. Such prevention method will keep the barrier substantially unaffected.
2. Prior Art
Present day building design practices call for the use of many glass windows and doors in our homes, schools, office buildings and other structures. These transparent windows and doors present a serious hazard to flying birds who by nature are not prepared to perceive the presence of such barriers. The problem is most acute in an area where a bird is able to see through a structure. Such condition would occur, for example, in the case of a corridor with facing exterior glass walls or in the case of a corner room of a building with glass windows on two sides. In sympathy with the birds who are injured or killed by these collisions, one would like to make it possible for the flying bird to avoid the transparent barrier by its own inherent instincts. At the same time, the glass windows and doors of our buildings serve an aesthetic and functional purpose and one would like to leave them as unaffected as possible.
Numerous devices are designed for the purpose of preventing birds from perching in certain places such as the ledges of buildings and window sills. Some such devices employ sharp spikes or elaborate ornaments to make the environment unsuitable and perhaps even dangerous for the presence of the bird. For example, U.S. Pat. No. 5,253,444 to Donoho et al. (1993). Other devices are designed for the purpose of preventing collisions between birds and flying aircraft. For example, U.S. Pat. No. 4,736,907 to Steffen (1988). These devices and methods all employ a means of scaring the birds away from the area of roosting and gathering. All of the inventions of these two categories just mentioned are not designed primarily for the protection of the bird and do not apply in any practical way to the problem addressed herein.
There are existing methods for protecting birds from other types of dangers. Devices have been designed to prevent a bird from electrocution when it lands on the crossbar of a power pole. See U.S. Pat. No. 4,359,844 to Hoggard et al. (1982) and U.S. Pat. No. 5,299,528 to Blankenship (1994). Also, an apparatus has been designed to protect birds by means of a physical barrier from the danger of alighting on a gas flue stack or from nesting inside the stack. See U.S. Pat. No. 5,291,707 to McDonald (1994). Such inventions which are intended to protect birds from particular types of dangers are hardly applicable to the case of transparent barriers. Nelson, U.S. Pat. No. 5,167,099 (1992), shows a device for deterring birds from nesting or roosting on an upwardly facing horizontal surface consisting of strings held in place by brackets. Nelson would not apply to the problem of transparent barriers since it would not apply to vertical barriers which are inherently the subject of the present invention. Numerous devices exist which are designed to scare birds with the image of a predator or the eyes of a predator and such. See JP 4-229,124 and JP 6-181,672. Such devices do not have a lasting effect as the wild birds tend to become complacent about the object over time (example: the familiar picture of the crow roosting on the scarecrow). It is also not clear how a scaring device such as these can be utilized to divert a bird in the dynamic circumstance of flying toward a transparent barrier. In any case, the present invention is far less elaborate and almost certainly more effective than the inventions cited.
Countryman, U.S. Pat. No. 2,603,485 teaches placing an image of a spider web on a window. The Countryman invention is intended as an amusing decoration and does not include the stabilimentum which is added to the web of certain spiders for the purpose of protecting the web from collisions by birds. It has been shown that even real webs which do not have the stabilimentum will not enjoy the same protection (Eisner and Nowicki). In any case, Countryman does not anticipate and does not teach that a spider web containing a stabilimentum placed on a transparent barrier will accomplish the purpose of the present invention.
There exists therefore a need for a simple, passive and inexpensive method for deflecting flying birds from the unique danger of collision with barriers which are invisible to the bird. It should be easy to install, unobtrusive and effective.
3. Objective
The principle objective of the present invention is to provide a method for causing a bird which is flying toward a transparent barrier--a danger unperceived by the bird--to think that it is flying toward a spider web--a danger which is perceived by the bird.
A further objective of the invention is to accomplish the principle objective, just stated, while interfering as little as possible with the function of the transparent barrier.